Guglielmi detachable coils (GDCs) are the gold standard for endovascular treatment of brain aneurysms. However, GDCs appear to be less effective in wide-necked aneurysms (> 4mm). We propose to develop a new, bio-active, bio-absorbable polymeric material (BPM) coil that improves aneurysm healing by accelerating clot maturation and organization within the aneurysm. We hypothesize that aneurysm healing can be controlled by using BPMs. LONG-TERM OBJECTIVE: To improve clinical management of brain aneurysms by overcoming the present limitations of GDC system. The knowledge of the bio-molecular cascade eliciting aneurysm healing will allow its manipulation and development of better embolic agents. IMMEDIATE OBJECTIVE: 1) Bio-molecular and histological evaluations of natural thrombus formation in surgically created aneurysm. Special attention will be paid on cytokine expression related to clot maturation. 2) In-vitro evaluation of physical, chemical and degradation properties of commercially available Polymers for potential application in brain aneurysm therapy. 3) Utilization of a lateral aneurysm model in swine to evaluate anatomical and histological effects of different bioabsorption properties of commercially available Polymers and their impact in aneurysm healing. 4) Transform current GDC technology to bioactive surface GDC (Hybrid BPM/GDC) and evaluation of angiographic and histological effectiveness of a Hybrid BPWGDC coil. 5) Development of a 100 percent bio-absorbablehio-active intravascular coil for endovascular embolization of intracranial aneurysms